Famotidine: Uses, Dosage, Side Effects & Precautions
Famotidine is an H2 blocker that reduces stomach acid and is used for GERD, peptic ulcers and heartburn. This guide covers famotidine uses, how it works, dosage, side effects, precautions, drug interactions, use in pregnancy and breastfeeding and its approximate price in India.
What is Famotidine?
Famotidine is an H2 receptor antagonist (H2 blocker) used to reduce stomach acid. It is commonly prescribed for conditions like gastroesophageal reflux disease (GERD) and peptic ulcers, and for relief of heartburn symptoms.
At a Glance
Aspect | Details |
Medicine class | H2 receptor antagonist (an acid reducer, not a traditional antacid) |
Main uses | GERD, duodenal and gastric ulcers, erosive esophagitis and short-term relief of heartburn symptoms |
How it works | Reduces the amount of acid the stomach makes. It usually begins working within about an hour, and how long the effect lasts varies with the dose, the formulation and the person. |
Strength commonly available in India | 20 mg tablets (for example, Famocid 20) |
Key safety point | Famotidine is cleared through the kidneys. People with moderate or severe kidney problems, and older adults, may need a lower dose. |
Pregnancy and breastfeeding | Can be used when clinically needed. The decision is made with your doctor. |
How Famotidine Works
Famotidine works by blocking histamine at the H2 receptors in the stomach, reducing acid production. With less acid, ulcers can heal and reflux symptoms such as heartburn ease.
When to Use Famotidine
- GERD: Reduces acid reflux symptoms.
- Erosive esophagitis: Used for esophagitis caused by GERD, diagnosed by endoscopy.
- Peptic ulcers: Helps heal ulcers in the stomach and the first part of the intestine (duodenum).
- Heartburn: Short-term relief of heartburn symptoms. Heartburn is a symptom, not a disease, and frequent or persistent heartburn should be checked by a doctor.
- Other uses: Reducing the risk of duodenal ulcers coming back, and conditions with very high acid production such as Zollinger-Ellison syndrome (under specialist care).
Famotidine Dosage
The doses below are general reference only. Take famotidine only as prescribed by your doctor.
- Adult dose (normal kidney function):
○ GERD: 20 mg twice daily
○ Duodenal ulcer: 40 mg once daily at bedtime, or 20 mg twice daily
○ Gastric ulcer: 40 mg once daily
○ Erosive esophagitis: 20 mg or 40 mg twice daily
- Treatment duration: This depends on the condition, the formulation and how you respond. Prescribing information describes courses of several weeks for ulcers, GERD and erosive esophagitis, but your doctor decides how long you should continue.
- Kidney function: Famotidine is cleared mainly by the kidneys, so blood levels are higher in people with reduced kidney function. A lower dose is recommended for moderate or severe kidney impairment (creatinine clearance below 60 mL/min), and your doctor may choose a different tablet strength or formulation.
- Older adults: The lowest effective dose is generally used, and kidney function is taken into account.
- Pediatric dose: Depends on the child’s age, weight, condition and the formulation used. The standard 20 mg and 40 mg tablets may not be appropriate for children under 40 kg, so doctors choose a more suitable form.
- How to take it: Once daily before bedtime, or twice daily in the morning and before bedtime. It can be taken with or without food and may be taken with antacids.
Take this medicine only as advised by your doctor or healthcare professional. Do not start, stop, or change the dose on your own.
Side Effects of Famotidine
- Common: Headache, dizziness, constipation, diarrhea.
- Other reported effects: Nausea and dry mouth.
- Contact your doctor promptly for:
○ confusion, hallucinations, agitation or seizures (more likely in older adults and people with kidney problems)
○ palpitations, fainting or lightheadedness
○ signs of a serious allergic reaction, such as swelling of the face or throat, or trouble breathing
Famotidine Precautions
Tell your doctor before taking famotidine if you:
- have ever had a serious allergic reaction to famotidine or another H2 blocker (this is a reason not to use it)
- have kidney problems
- are an older adult
- take other medicines
Symptom relief does not rule out stomach cancer. Feeling better on famotidine does not rule out a more serious stomach problem, including gastric cancer. If symptoms do not improve, return soon after treatment, keep coming back, or worry you, see your doctor for evaluation rather than continuing to treat them on your own.
Famotidine Drug Interactions
- Tizanidine: Famotidine may raise tizanidine blood levels (it is a weak CYP1A2 inhibitor), which can cause low blood pressure, slow heartbeat or excessive drowsiness. Combined use should be avoided if possible.
- Medicines that need stomach acid to be absorbed: By lowering stomach acid, famotidine can reduce how well some medicines are absorbed and make them less effective. The advice differs by medicine.
○ Use with dasatinib, delavirdine, cefditoren and fosamprenavir is not recommended.
○ For atazanavir, erlotinib, ketoconazole, itraconazole, nilotinib, rilpivirine and ledipasvir/sofosbuvir, the prescribing information gives specific administration instructions, so your doctor or pharmacist will advise how to take them.
Tell your doctor or pharmacist about all prescription medicines, OTC medicines, supplements and herbal products you take. This list is not complete.
Famotidine in Pregnancy and Breastfeeding
- Pregnancy: Famotidine is widely used for stomach acid symptoms in pregnancy. Observational studies have not found an increased risk of major birth defects with H2 blockers, including famotidine. Well-controlled studies in pregnant women are limited. Famotidine can be used during pregnancy when clinically needed, and the decision should be made with your doctor.
- Breastfeeding: Only small amounts pass into breast milk, lower than doses given to newborn infants, and adverse effects in breastfed infants are not expected. Tell your doctor that you are breastfeeding so they can advise you.
Famotidine Brands, Strengths and Approximate Price in India
Common Brands in India: Famocid, Topcid, Facid. A well-known US brand is Pepcid.
Brand | Strength | Pack size | Approximate price |
Famocid | 20 mg tablet | Strip of 14 tablets | ₹1–₹12 |
Prices vary by brand, pharmacy, location, pack size and discounts. Tablet strength is not the same as your dose, so take only what your doctor prescribes.
How HealthPil Can Help
HealthPil connects you to gastroenterologists for comprehensive care. Medicines should be started, adjusted, or stopped only under the guidance of a qualified healthcare professional. If you have questions about this medicine, its side effects, or your treatment plan, you can consult a doctor through HealthPil.
FAQ
Is Famotidine safe for long-term use?
Famotidine is usually prescribed for a limited period. Studies for preventing ulcer recurrence went up to one year. Long-term use should be monitored, especially in older adults and people with kidney problems, who often need a lower dose. Do not use it long term on your own, and see your doctor if symptoms keep returning.
Is famotidine an antacid?
Not in the traditional sense. Famotidine is an H2 blocker that reduces how much acid the stomach makes. It may be taken together with antacids.
How long does famotidine take to work?
Its acid-reducing effect begins within about an hour, reaches its peak in one to three hours, and lasts roughly 10 to 12 hours. Ulcer healing takes longer, so follow the course your doctor prescribes.
Can I take famotidine during pregnancy or breastfeeding?
Only if clearly needed and on your doctor’s advice, as data are limited.
Can I take famotidine with other medicines?
Some medicines, such as tizanidine and certain antivirals, antifungals and cancer medicines, can be affected. Always check with your doctor or pharmacist first.
